Renting a Car

Renting a car gives you the freedom to tour the island and access to trail heads that you just can't get with a bus, and light "K"-class cars are a wonderful option for navigating narrow mountain roads.

Documents:

1. Driver's Licence
2. Official Translation of Your Driver's Licence: You need this if your license is from Taiwan, France, Germany, Switzerland, Belgium, Estonia, Monaco, or Slovenia. Your license is perfectly fine in Japan, so long as you also carry an official translation. Check with your country's embassy. Otherwise you can get one through the Japanese Automobile Federation for ¥3000. Do this before you come to Yakushima.
3. International Drivers' License: Everybody else who has been in Japan for less than a year does not need a translation, but does need an international drivers' license. This is issued (usually for a modest fee) in the country that issued your drivers' license, NOT JAPAN. You will need to get it before you leave home.
4. Passport

Where to Rent:

You have a lot of choices here, from national companies like Times and Toyota (which, I am told, may be able to provide a navi/GPS system in foreign languages) and discount companies like Niko-Niko, regional companies like Nansei (which, I believe, has an English-speaker working in Yakushima), local companies like Matsubanda, and tiny companies like Kuriyama and Shinjiyama (which doesn't employ English speakers, but offers most of the documents in English). Many of these companies offer pickup and drop-off from the ports, and let you leave the car at designated locations on the east side of Yakushima. However, at the time of writing, none of these companies are open at night. You will have to return the car during business hours or pay to keep it until the morning. 

Extra costs:

• Get the extra insurance. This usually costs around ¥1000/day and while it may not cover some things like tire punctures, when I think about the number of scrapes my guests have incurred, I can definitely say it's worth it.
• Plan your last gasoline stop. Remember that gasoline stands also close at night (9 at the latest, but earlier for most places). If you want to return your car before the gasoline stand opens, (for example, if you are leaving Yakushima on the first boat out, or if you're going hiking early in the morning) you're going to have to pay extra in advance. In fact, most rental shops may not allow this if the gasoline calculation is too complicated.
• Maybe you don't need a GPS. If you have someone sitting in the passenger seat with a smartphone, you should be fine. Anyways, there's only one major road that goes around Yakushima, and it may be better to rely on directions than on GPS for the smaller roads.

Driving:

• Rules: Left side of the road, obviously. If you've never driven in Japan, I advise reviewing basic signs like Stop and No Parking. If you have trouble finding a parking space for a store, or if you're not sure if a parking lot is public or not, just ask.
• Seat Belts and Child Seats: Everyone is required to wear seat belts. Children under 6 must use child seats (or junior seats), which car rental shops can provide upon request.
• Hazards: In addition to wildlife and pedestrians, (Pedestrians always have the right-of-way!) there is often a lot of construction, often with temporary traffic lights that you'll need to stop for. In the winter, roads in the mountains can get icy when the temperatures drop. It's best to just avoid icy/snowy roads here.
• The West Forest Road and interior roads often go down to one lane, so you'll need to be ready to stop at all times and confident in reversing around turns.

Road Closures:

• Arakawa Trail Head: From March through November, you may not drive to the Arakawa Trail Head (to hike to Jomon Sugi). There's just too much traffic, so you'll have to park at the Museum (near Anbo) and take a shuttle bus instead.
• West Forest Road (西部林道/Seibu Rindoh): Due to shifting ground, this road is closed at night from 5pm to 7am.
• Rock-slides, weather-warnings, ice, and snow can also cause unscheduled road closures.